Heat Pump

ABSTRACT

A heat pump intended to operate in a space (S), includes a compressor ( 3 ), preferably located in the space (S), and a first inlet conduit ( 10 ) for supplying air/gas to the compressor ( 3 ). The heat pump also includes a Ranque generator ( 1 ), a connection conduit ( 5 ) extending between the compressor ( 3 ) and the Ranque generator ( 1 ), the connection conduit ( 5 ) transferring compressed air/gas to the Ranque generator ( 1 ), a first outlet conduit ( 7 ) for air/gas emanating from the hot side of the Ranque generator ( 1 ), the first outlet conduit ( 7 ) emerging inside the space (S) or being connected to a first heat exchanger ( 211 ) inside the space (S 2 ), and a second outlet conduit ( 9 ) for air/gas emanating from the cold side of the Ranque generator ( 1 ), the second outlet conduit ( 9 ) emerging outside the space (S).

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a heat pump that is intended to operate in a space, said heat pump comprising a compressor and an inlet conduit for supplying air/gas to the compressor.

PRIOR ART

It is previously known a great number of different heat pumps that normally comprise a compressor, an evaporator, a condenser and an expansion valve. As regards heat pumps with air it is a well known fact that they have low efficiency when the outdoor air has low temperature.

A Ranque generator is a device that was invented by George Ranque in the 1930's, a Ranque generator generally having the function that it divides a compressed air- or gas stream into a cold air- or gas stream and a hot air- or gas stream. The Ranque generator will be described more in detail below.

From for instance U.S. Pat. No. 6,334,841 a centrifuge for biological products is previously known, said centrifuge comprising a device for cooling the space where centrifuging takes place. In this last mentioned device a Ranque generator is included, said generator producing the cold air that is used in the cooling.

OBJECTS AND FEATURES OF THE INVENTION

A primary object of the present invention is to present a heat pump of the type defined above, said heat pump having a coefficient of performance that is higher than one.

A further object of the present invention is to present a heat pump that is extremely environment friendly since it is completely free from CFC or other gases that are hazardous to the environment when it is used in an open system. If it is used in a closed system the gases that are used will not come into contact with the environment.

Still an object of the present invention is to present a heat pump having small dimensions.

A further object of the present invention is to present a heat pump that is easy to install.

At least the primary object of the present invention is realized by means of a device that has been given the features of the appending independent claim 1. Preferred embodiments are defined in the dependent claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Below a number of embodiments of the invention will be described, reference being made to the accompanying drawings, where:

Figure A schematically shows a Ranque generator;

FIG. 1 shows the schematic structure of a first embodiment of a heat pump according to the present invention;

FIG. 2 shows the schematic structure of a second embodiment of a heat pump according to the present invention;

FIG. 3 shows the schematic structure of a third embodiment of a heat pump according to the present invention;

FIG. 4 shows the schematic structure of a fourth embodiment of a heat pump according to the present invention;

FIG. 5 shows the schematic structure of a fifth embodiment of a heat pump according to the present invention; and

FIG. 6 shows the schematic structure of a sixth embodiment of a heat pump according to present invention.

DETAILED DESCRIPTION OF PRIOR ART AND PREFERRED EMBODIMENTS OF THE PRESENT INVENTION

The Ranque generator shown in figure A comprises a chamber C, a first outlet pipe P1 emanating from the chamber C and a second outlet pipe P2 emanating from the chamber, said outlet pipes P1 and P2 generally being attached to opposite sides of the chamber C. The chamber C defines a space that generally has circular cylindrical cross section relative to an axis in the plane of the paper. In operation of the Ranque generator compressed air or gas is supplied to the chamber C.

The supplied air or gas will flow along the circular cylindrical limiting surface of the chamber at a high speed, about 1.000.000 revolutions/min. Due to means provided in the chamber C there is a division in an outer hot air- or gas stream and an inner cold air- or gas stream. Both these air- or gas streams are deviated in different directions via the two outlet pipes P1 and P2. The difference in temperature between the cold air- or gas stream and the hot air- or gas stream is considerable. In exemplifying and non-restricting purpose it may be mentioned that if compressed air of 7 bar is supplied to the chamber C a hot air stream could be achieved with a temperature that is about 50° C. higher than the supplied air and a cold air stream with a temperature that is about 50° C. lower than the supplied air. If there is a division in hot and cold air streams of different volume the difference in temperature relative to the supplied air will decrease if the volume increases.

The Ranque generator represents prior art and will not be described in further detail.

In FIG. 1 a space S is shown schematically, a first embodiment of a heat pump according to the present invention being provided in said space S. The space S may for instance constitute a residential building.

The heat pump according to the present invention, shown in FIG. 1, comprises a Ranque generator 1, a compressor 3, a connection conduit 5 to the Ranque generator 1, a first outlet conduit 7 from the Ranque generator 1, a second outlet conduit 9 from the Ranque generator 1 and a first inlet conduit 10 to the compressor 3.

The connection conduit 5 extends between the compressor 3 and the Ranque generator 1. The first outlet conduit 7 emerges in the space S while the other outlet conduit extends through the limiting wall of the space S and thus emerges in the open air. The first inlet conduit 10 extends from the open air outside the space S to the compressor 3. The components in the dashed square in FIG. 1 are thus included in the heat pump according to the present invention.

The heat pump shown in FIG. 1 functions in such a way that outside air is supplied to the compressor 3 via the first inlet conduit 10. The compressor 3 compresses this outside air and thus supplies compressed air to the Ranque generator 1. In a way that has been described above the Ranque generator 1 transfers this compressed air into a hot air stream, that is discharged into the space S via the first outlet conduit 7, and a cold air stream that is supplied to the outdoor air via the second outlet conduit 9.

The enthalpy in the hot air stream will thus be of use to the space S. In this connection it should also be noticed that the heat that is generated when the compressor 3 compresses the air will be of use to the space S. Losses due to the efficiency of the compressor 3 is also of use to the space S in the shape of heat.

In the embodiment according to FIG. 2 the heat pump according to the present invention comprises the corresponding components as the embodiment according to FIG. 1, i.e. a Ranque generator 101, 1 compressor 103, a connection conduit 105 to the Ranque generator 101, a second outlet conduit 109 from the Ranque generator 101 and a first inlet conduit 110 to the compressor 103.

The heat pump shown in FIG. 2 functions in such a way that indoor air is supplied to the compressor 103 via the first inlet conduit 110. The compressor 103 compresses this indoor air and thus supplies compressed air to the Ranque generator 101. In a way that has been described above the Ranque generator 101 transfers this compressed air into a hot air stream, that is discharged into the space S1 via the first outlet conduit 107, and a cold air stream that is supplied to the outdoor air via the second outlet conduit 109.

As regards the arrangement shown in FIG. 2 no positive pressure is generated in the space S since the air that is supplied to the compressor 103 constitutes indoor air that is taken from the space S1. If all air is taken from the space S1 a negative pressure will be generated in the space S1. This brings about that air will flow into the space S1 through vents and the like, a vent V1 being indicated in FIG. 2. Since outdoor air is sucked in through the vent V1 the air change will generally be good in the embodiment according to FIG. 2.

The embodiment shown in FIG. 3 of a heat pump according to the present invention rely on a closed system that comprises two heat exchangers. The components in the dashed square of FIG. 3 are thus included in the heat pump according to the present invention. The heat pump according to FIG. 3 is installed in a space S2 and also comprises a Ranque generator 201 and a compressor 203. A connection conduit 205 extends from the compressor 203 to the Ranque generator 201. From the hot side of the Ranque generator 201 a first outlet conduit 207 exits, said first outlet conduit 207 being connected to a first heat exchanger 211 that is located inside the space S2. A first inlet conduit 210 to the compressor 203 exits from a second heat exchanger 213 that is located outside the space S2. A second inlet conduit 212 extends from the first heat exchanger 211 and joins the first inlet conduit 210 upstream the compressor 203. The second heat exchanger 213 is connected to the cold side of the Ranque generator 201, this being effected by means of a second outlet conduit 209 from the Ranque generator 201.

The heat pump, shown schematically in FIG. 3, functions in the following way. Air/gas is supplied to the compressor 203 via the first inlet conduit 210 and a second inlet conduit 212, this supplied air/gas is a mixture of air/gas from the first heat exchanger 211 and air/gas from the second heat exchanger 213. The air/gas that comes from the second heat exchanger 213 is heated by the outdoor air while the air/gas that comes from the first heat exchanger 211 has emitted heat to the space S2, i.e. said air/gas is chilled. These two volumes of air/gas are now mixed and supplied to the compressor 203 and then the supplied mixture is compressed by the compressor 203. From the compressor 203 compressed air is supplied to the Ranque generator 201, said supplied compressed air in a known way being divided into a hot air stream that is deflected via the first outlet conduit 207 and a cold air stream that is deflected via the second outlet conduit 209.

The hot air-/gas stream that is discharged via the first outlet conduit 207 passes the first heat exchanger 211 and the hot air-/gas stream emits heat to the space S2. The chilled air-/gas stream then continues in the second inlet conduit 212 and is mixed with the air-/gas stream in the first inlet conduit 210, upstream the compressor 203.

The cold air/gas that is discharged from the Ranque generator 201 flows in the second outlet conduit 209 and passes through the second heat exchanger 213. Since the air/gas that flows in the outlet conduit 209 is substantially chilled it will be heated by the outdoor air when passing through the second heat exchanger 213, even if the outdoor air has a comparatively low temperature. When the air/gas has pass the second heat exchanger 213 it is supplied to the compressor 203 via the first inlet conduit 210. As has been pointed out above a mixture will then take place with the air/gas that emanates from the first heat exchanger 211.

The embodiment of a heat pump according to the present invention that is shown in FIG. 4 is a variant of the embodiment according to FIG. 3. The heat pump according to FIG. 4 is installed in a space S3, said heat pump also comprising a Ranque generator 301 and a compressor 303. A connection conduit 305 extends from the compressor 303 to the Ranque generator 301. From the hot side of the Ranque generator 301 a first outlet conduit 307 exits, said first outlet conduit 307 being connected to a first heat exchanger 311 that is located inside the space S3. A first inlet conduit 310 to the compressor 303 emanates from a second heat exchanger 313 that is located outside the space S3. A second inlet conduit 312 extends from the first heat exchanger 313 and joins the first inlet conduit 310 to the compressor 303. This first inlet conduit 310 emanates from the first heat exchanger 311 that is located outside the space S3. The first inlet conduit 310 is “coiled” around the compressor 303 and the connection conduit 305 before the first inlet conduit 310 joins the second inlet conduit 312 upstream the compressor 303. This arrangement has the aim to cool the connection conduit 305 and the compressor 303. Thereby, the heat losses are reduced and the temperature in the first outlet conduit 307 is raised. The second heat exchanger 313 is connected to the cold side of the Ranque generator 301, this being effected by means of a second outlet conduit 309 from the Ranque generator 301.

The embodiment of a heat pump according to the present invention that is described in FIG. 4 functions in principle in the same way as the embodiment according to FIG. 3.

In the embodiment shown in FIG. 5 a conventional air heat pump is completed with a heat pump according to the present invention. The conventional air heat pump according to FIG. 5 comprises a third heat exchanger 415 and a fourth heat exchanger 416. The third heat exchanger 415, that in principle constitutes an evaporator, is located in the open air outside a space in which the conventional air heat pump is operating while the fourth heat exchanger 416, that in principle constitutes a condenser, is located in the air in the space, in which the conventional air heat pump operates. A first transferring conduit 417 extends from the third heat exchanger 415 to the fourth heat exchanger 416. In this first transferring conduit 417 a compressor 418 is provided, said compressor 418 being related to the conventional air heat pump. A second transferring conduit 419 extends from the fourth heat exchanger 416 to the third heat exchanger 415. An expansion valve 420 is provided in the second transferring conduit 419. A first fan 421 is related to the third heat exchanger 415 and a second fan 422 is related to the fourth heat exchanger 416. These fans 421, 422 guarantee sufficient air movement in connection with the respective heat exchanger 415, 416. When the conventional air heat pump is operating an energy storing medium is brought to circulate through the third heat exchanger 415, the first transferring conduit 417, the fourth heat exchanger 416 and the second transferring conduit 419. The energy storing medium, e.g. CFC, is compressed by the compressor 418 that is related to the air heat pump before the energy storing medium passes through the fourth heat exchanger 416 where heat is emitted to the space, in which the conventional heat pump operates. The third heat exchanger 415 absorbs heat from the outdoor air. At low temperatures, especially below −10° C., the energy exchange is low. In order to improve this energy exchange a further heat pump is used in accordance with the principle of the present invention, said further heat pump comprising a Ranque generator. As is evident from FIG. 5 the outdoor third heat exchanger 415, with its components, is located in a space S4, in which also the further heat pump is located, said further heat pump comprising a Ranque generator. As is indicated by the arrows A1 and A2 an air stream takes place through the space S4 in connection with the operation of the first fan 421.

In FIG. 5 it is schematically shown how a heat pump according to the present invention is provided in the space S4. This heat pump comprises a Ranque generator 401, a compressor 403, a connection conduit 405 to the Ranque generator 401, a first outlet conduit 407 from the Ranque generator 401, a second outlet conduit 409 from the Ranque generator 401 and a first inlet conduit 410 to the compressor 403. The hot air stream that emanates from the Ranque generator 401 is discharged via the first outlet conduit 407 and heats the air that surrounds the third heat exchanger 415. The cold air stream that emanates from the Ranque generator 401 is discharged via the second outlet conduit 409 that emanates outside the space S4.

In the embodiment according to FIG. 6 only one space S5 is shown, said space S5 holding the third heat exchanger 515 of a conventional air heat pump and a heat pump according to the present invention. A compressor 518 and an expansion valve 520 are related to the conventional air heat pump. As is evident from FIG. 6 the first fan 521 heats a first portion of the third heat exchanger 515 while the heat pump according to the present invention heats a second portion of the third heat exchanger 515. The heat pump according to the present invention comprises a Ranque generator 501, a compressor 503, a connection conduit 505 to the Ranque generator 501, a first outlet conduit 507 from the Ranque generator 501, a second outlet conduit 509 from the Ranque generator 501 and a first inlet conduit 510 to the compressor 503. The hot air stream that exits from the Ranque generator 501 is discharged via the first outlet conduit 507 and heats the upper portion of the third heat exchanger 515. The cold air stream that exits from the Ranque generator 501 is discharged via the second outlet conduit 509 that emerges outside the space S5.

In the embodiment shown in FIG. 6 the compressors 503 and 518 are driven by a common power source, this being illustrated by the interconnection of the compressors 503 and 518. Within the scope of the invention it is feasible that the compressors 503 and 518 each are related to a separate power source.

Generally, in the embodiments described above of a heat pump according to the present invention, said heat pump comprising a Ranque generator and a compressor. Preferably, a worm compressor is used that has a high capacity and a regular air flow rate. The heat that is generated when the compressor compresses the air will be of use to the space, in which the heat pump is installed.

Feasible Modifications of the Invention

In the embodiments of the invention described above the compressor 3; 103; 203; 303; 403; 503 is located in the space S; S1; S2; S3; S4; S5. However, within the scope of the present invention is also feasible that the compressor is located outside the space, in which the heat pump operates.

The heat pump system according to the present invention may for instance be equipped with a temperature sensor to register the temperature difference between the hot and the cold side of the Ranque generator 1; 101; 201; 301; 401; 501, the rotational frequency of the compressor 3; 103; 203; 303; 403; 503 being regulated dependent on said measured temperature difference.

The compressor 3; 103; 203; 303; 403; 503 that is used in a heat pump according to the present invention may be water cooled, the heat that is generated adjacent to the compressor 3; 103;, 203; 303; 403; 503 may be taken care of via a heat exchanger.

In the embodiment according to FIG. 3 a second heat exchanger 213 is provided outside the space S2, in the free air. This second heat exchanger 213 may also the located in water, for instance in a lake, it might be embedded in the ground or located in the bedrock. Is also feasible that the second the exchanger 213 is designed as a solar collector. Generally, the purpose of the exemplified arrangements is to achieve an improved heating of the air/gas compared to the location of the second heat exchanger 213 in the open air.

In the embodiment according to FIG. 3 it is also feasible, within the scope of the present invention, that the first heat exchanger 211 is used to heat hot service water or water in a system for hot water heating.

In the embodiment according to FIG. 3 it is feasible, within the scope of present invention, that the second outlet conduit 209 is used to cool for instance a refrigerator, a freezer or an underground storehouse.

Within the scope of the present invention is also feasible that one or both heat exchangers are integrated with the heat pump according to the present invention, i.e. the compressor, the Ranque generator and at least one of the heat exchangers form a unit in the space, in which the heat pump is intended to operate. If the heat exchanger that is connected to the cold side of the Ranque generator is integrated in this unit the cold air that is generated in the area of this heat exchanger must be taken care of in a suitable way, this being for instance effected by means of a fan that transports the cold air to the outside of the space, in which the heat pump operates.

The embodiments shown in FIGS. 5 and 6 are illustrated with a conventional air heat pump. Within the scope of the present invention it is however feasible that the heat pump according to the present invention cooperates with some other type of conventional heat pump, for instance an air-water heat pump or a geothermal heat pump. 

1. Heat pump that is intended to operate in a space (S; S1; S2; S3; S4; S5), said heat pump comprising a compressor (3; 103; 203; 303; 403; 503) and a first inlet conduit (10; 110; 210; 310; 410; 510) for supplying air/gas to the compressor (3; 103; 203; 303; 403; 503), characterised in that the heat pump comprises a Ranque generator (1; 101; 201; 301; 401; 501), a connection conduit (5; 105; 205; 305; 405; 505) extending between the compressor (3; 103; 2203; 303; 403; 503) and the Ranque generator (1; 101; 201; 301; 401; 501) to transfer compressed air/gas to the Ranque generator (1; 101; 201; 301; 401; 501), a first outlet conduit (7; 107; 207; 307; 407; 507) for air/gas emanating from the hot side of the Ranque generator (1; 101; 201; 301; 401; 501), said first outlet conduit (7; 107; 207; 307; 407; 507) emerging inside the space (S; S1; S4; S5) or being connected to a first heat exchanger (211; 311) inside the space (S2; S3), and a second outlet conduit for air/gas emanating from the cold side of the Ranque generator (1; 101; 201; 301; 401; 501), said second outlet conduit (9; 109; 209; 309; 409; 509) emerging outside the space (S; S1; S4; S5) or being connected to a second heat exchanger (213; 313).
 2. Heat pump according to claim 1, characterised in that the second heat exchanger (213; 313) is located outside the space (S2; S3).
 3. Heat pump according to claim 1, characterised in that the inlet of the inlet conduit (10; 410; 510) is located in the open air outside the space (S; S4; S5).
 4. Heat pump according to claim 1, characterised in that the inlet of the first inlet conduit (110) is located in the open air inside the space (S1).
 5. Heat pump according to claim 1, characterised in that the first inlet conduit (210; 310), at its end remote from the compressor (203; 303), is connected to the second heat exchanger (213; 313) outside the space (S2; S3).
 6. Heat pump according to claim 5, characterised in that the first inlet conduit (310) extends around the compressor (303) and the connection conduit (305), said connection conduit (305) transferring compressed air/gas to the Ranque generator (301).
 7. Heat pump according to claim 5, characterised in that a second inlet conduit (212; 312) that emanates from the first heat exchanger (211; 311) joins the first inlet conduit (210; 310) upstream the compressor (203; 303).
 8. Heat pump according to claim 1, characterised in that the compressor constitutes a worm compressor (3; 103; 203; 303; 403; 503).
 9. Heat pump according to claim 1, characterised in that it comprises a temperature sensor to register the temperature difference between the hot and cold side of the Ranque generator (1; 101; 201; 301; 401; 501), and that the heat pump also comprises means to regulate the rotational frequency of the compressor (3; 103, 203, 303; 403; 503) dependent on the measured temperature difference.
 10. Heat pump according to claim 1, characterised in that the space (S4; S5) also includes a third heat exchanger (415; 515) that constitutes a part of a conventional heat pump.
 11. Heat pump according to claim 2, characterised in that the inlet of the inlet conduit (10; 410; 510) is located in the open air outside the space (S; S4; S5).
 12. Heat pump according to claim 2, characterised in that the inlet of the inlet conduit (10; 410; 510) is located in the open air outside the space (S; S4; S5).
 13. Heat pump according to claim 2, characterised in that the inlet of the inlet conduit (10; 410; 510) is located in the open air outside the space (S; S4; S5).
 14. Heat pump according to claim 13, characterised in that the first inlet conduit (310) extends around the compressor (303) and the connection conduit (305), said connection conduit (305) transferring compressed air/gas to the Ranque generator (301).
 15. Heat pump according to claim 6, characterised in that a second inlet conduit (212; 312) that emanates from the first heat exchanger (211; 311) joins the first inlet conduit (210; 310) upstream the compressor (203; 303). 